Implementation fidelity in adolescent family-based prevention programs: relationship to family engagement.

Reliability and validity of intervention studies are impossible without adequate program fidelity, as it ensures that the intervention was implemented as designed and allows for accurate conclusions about effectiveness (Bellg AJ, Borrelli B, Resnick B et al. Enhancing treatment fidelity in health behavior change studies: best practices and recommendations from the NIH behavior change consortium. Health Psychol 2004; 23: 443-51). This study examines the relation between program fidelity with family engagement (i.e. satisfaction and participation) in family-based prevention programs for adolescent alcohol, tobacco or other drug use. Families (n = 381) were those with an 11- to 12-year-old child enrolled in Kaiser Permanente in the San Francisco area. Families participated in one of two programs: Strengthening Families Program: For Parents and Youth 10-14 (SFP) (Spoth R, Redmond C, Lepper H. Alcohol initiation outcomes of universal family-focused preventive interventions: one- and two-year follow-ups of a controlled study. J Stud Alcohol Suppl 1999; 13: 103-11) or Family Matters (FM) (Bauman KE, Ennett ST. On the importance of peer influence for adolescent drug use: commonly neglected considerations. Addiction 1996; 91: 185-98). Fidelity was assessed by: (i) adherence to the program manual and (ii) quality of implementation. No relationships were found for FM, a self-directed program. For SFP, higher quality scores were related to higher parent satisfaction. Higher adherence scores were related to higher satisfaction for youth, yet surprisingly to lower satisfaction for parents. Parent sessions involve much discussion, and to obtain high adherence scores, health educators were often required to limit this to implement all program activities. Findings highlight a delivery challenge in covering all activities while allowing parents to engage in mutually supportive behavior.